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From: jwag@moose.asd.sgi.com (Chris Wagner)
Newsgroups: comp.sys.sgi
Subject: Re: Arenas
Message-ID: <1991Mar27.162510.19842@odin.corp.sgi.com>
Date: 27 Mar 91 16:25:10 GMT
References: <1964@mira.cs.nps.navy.mil>
Sender: news@odin.corp.sgi.com (Net News)
Reply-To: jwag@moose.asd.sgi.com (Chris Wagner)
Organization: Silicon Graphics, Research & Development
Lines: 27

In article <1964@mira.cs.nps.navy.mil>, pratt@mira.cs.nps.navy.mil
(david pratt) writes:
> Greetings,
>    Thanks to everyone who answered my posting about VAX -> SGI format
>  conversions. I have two more questions on a new topic, arenas.
>    1. It seems that only eight processes can access an arena. I have run
> several test and have not been able to get the ninth process to connect. Is 
> there a way around this?
>    2. I want to create an arena that two different users can access.
Once again
> I get a no go (Permission denied). I have tried changing the protection on 
> the file and that doesn't work. Any ideas? I know this can create a security
> problem for some applications.
>    As always, any help is greatly appreciated.           

Look at usconfig(CONF_MAXUSERS) - set that to the # you want BEFORE
calling usinit.

As for the permissions, that is a bug/feature that has been fixed
in 4.0. In 4.0 you can now set the permissions on  the arena and the underlying
hardware lock devices.

The only work around I can think of is to change the mode on both the arena
file AND the /dev/hl/xxx file that is associated with that arena.


Chris Wagner